1. Field of the Invention
The present invention relates to a combustion apparatus that ignites a burner after the prepurge of a combustion chamber.
2. Description of the Related Art
There has hitherto been known a combustion apparatus comprising a burner, a CO sensor, and combustion control means that stops the combustion of the burner when the CO sensor detects carbon monoxide of a prescribed concentration or higher during the combustion of the burner (refer to Japanese Patent No. 3138353, for example).
According to this combustion apparatus, when the CO sensor detects carbon monoxide generated by the incomplete combustion of the burner, it is possible to prevent an increase in the carbon monoxide concentration by stopping the combustion of the burner.
However, because the CO sensor of the conventional combustion apparatus is intended for detecting the carbon monoxide concentration, it does not have performance high enough to detect combustible gasses other than carbon monoxide. For this reason, for example, in a case where the user handles a volatile fuel, such as gasoline, and a combustible gas becomes present near the air supply port of the combustion apparatus, it has been difficult to detect this combustible gas. And if the combustion apparatus is operated when the combustible gas is present near the air supply port like this, it might be thought that the combustible gas catches fire from an electric spark that might be generated by the energization of a fan and by the ignition of the burner.